Protection means



Jian. H5, i945. J. N. GooD 2,367,575

Jan. 16,

J. N. GOOD PROTECTION MEANS Filed April l, 1942 2 Sheets-Sheet 2 INVENTOR JOHN N. GOOD ATTORNEY Patented Jan. 16, 1945 PROTECTION MEANS John N. Good Wilmerding, Pa., assignor to The Westinghouse Air Brake Company, Wihnerding, Pa., a corporation of Pennsylvania Application April 1, 1942, Serial No. 437,211

(Cl. 303-18) y 23 Claims.

This invention relates to protection means for fluid pressure brakes, and more particularly for locomotive fluid pressure brakes.

For controlling the fluid pressure brakes on a train, the loco-motive is provided with a brake valve device, having a normal release or running position in which iuid under pressure is supplied from the main reservoir to the brake pipe by way of a feed valve device, to maintain the pressure in the brake pipe at a predetermined degree.

Sometimes on a long train, a section of the train may become detached without the engineer becoming aware of the fact, thus opening the brake pipe to the atmosphere. If, under such conditions, the brake valve device is not moved from the normal release or running position to a position to cut off the flow of fluid from the main reservoir to the brake pipe, the flow of fluid from the reservoir will continue until the reservoir pressure is depleted or reduced so low as to make it unsafe for the train to proceed.

It is the principal object of the invention to provide improved means for automatically cutting off the iiow of fluid from the main reservoir to Jche brake pipe in the event of an undesired parting of the train, with the brake valve device in normal release or running position.

As is well known by those skilled in the art some locomotive brake equipments employ means controlled by traflic or signal conditions in a railway system for controlling the brakes on the locomotive and cars of a train independently of the usual automatic brake valve device.

In Patent No. 2,256,283, issued to Ellis E. Hewitt and Donald L. McNeal on September i6, 1941, there is disclosed apparatus of the above type which embodies an engineers brake valve device operative manually to control the brakes on the train and an automatic train control valve device comprising an application'valve device which is adapted to respond to an unfavorable track signal to automatically effect a reduction in brake pipe pressure to apply the brakes on the train.

The automatic train control valve device is also provided with a brake pipe cut-ofi valve device for controlling the supply of fluid under pressure to the brake pipe-in running position of the brake valve device and is controlled by the application valve device, -whereupon operation of the application valve device in response to an unfavorable track signal to elect a reduction in brake pipe pressure, the cut-off valve device is operative to cut 01T the supply of :duid under pressure from the main reservoir to the brake pipe by wayof the feed valve device. However, in the event that there is a break-in-two of the train or if the brake pipe should become ruptured, the brake pipe cut-off valve device will not operate to cut off the supply of fluid under pressure to the brake pipe unless a brake application has been initiated by the brake application'valve device as above described.

Another object of the invention is therefore to provide an improved cut-off valve device of this type which is operative to cut off the flow of fluid from the main reservoir to the brake pipe in the event of a break-in-two of the train.

Still another object of the invention is to provide an improved cut-olf valve device so designed and constructed as to cut off the flow of fluid t0 the brake pipe upon either operation of the application valve device to initiate an application of the brakes or in the event of a break-in-two of the train.

Other objects and advantages will be apparent from the following more detailed description of the invention.

In the accompanying drawings Fig. 1 is a digrammatic View partly in section of a locomotive brake equipment embodying one form of the invention.

Fig. 2 is a diagrammatic view partly in section of a locomotive brake equipment embodying another form of the invention.

Except for the improvements therein, the apparatus shown in the drawings may be the same as that disclosed in the above referred to Hewitt' and McNeal patent, and for the sake of simplicity and ease of understanding only those parts which are considered essential to a complete and comprehensive understanding of Ithe invention will be described.

Description` of the embodiment shown in Fig. 1

As shown in Fig. 1 of the drawings, the locomotive brake equipment comprises a main reservoir l, a feed valve device 2, an engineers brake valve device 3, a brake pipe 4, a train signal pipe 5, an

automatic train control valve device 6 having anapplication valve portion 1 and a brake pipe cutoif valve portion 8.

The main reservoir l is of the usual well known type constructed and arranged to store duid under pressure which is supplied thereto by the` usual compressor, no-t shown.

The feed valve device 2 is of standard construction and operative in the usual manner to supply fluid Vfrom the main reservoir l to the engineers brake valve device 3 at a reduced pressure.

The engineers -brake valve device 3, which is provided for manual operation to control the brakes on the locomotive and cars of a traineither by straight air through a control pipe 9 or automatically through the medium of brake pipe 4, is substantially the same as that disclosed in Baterit.2,ll`06;483 issued to lEllis E. iHewitt on January V.9.5, 1938. Accordingly, only those parts of the engineers brake valve device 3 are shown in the drawings which are essential to the operation and a clear understanding fof the present invention.

As shown in Fig. 1 of the drawings, 'the 'engineers brake valve device "3 comprises .a pipe bracket I upon which is mounted a rotary valve casing section II which supports a straight 4air application and release valve portion I2. The rotary valve casing section II has a chamber I3` which is .connected .fthrough afpassage I4 containing a `ball check valve :I5 to ,azfeed vvalve pipe IE, :which pipe is adapted to bepsupplied with duid, lat a reduced pressure, zfromlthe'mainmeservoir I by `operation of the feed :valve .device :2.

In Achamber 1I 3 there is l,provided .nzrotary valve I6 for controlling ,the brakes on :the locomotive and a train in :thezusual Ymannerzthrough variations in the ipressureiof fluid in the brake pipe 4 upon .operationaof the valve towthe Vdifferent control positions vby Tthe `engineer fthrough the use of a brake .valve handle '.I'1.

The Vautomatic train control valve rdevice 5 comprises a `pipe .bracket in `which there :is included in the 'brake :pipe cut-off valve portion 8, and upon lwhich mounted the application valve portion 1. This automatic `train control valve device amayzbe similar 'to ;tha't :disclosed in our Patent y2,256,283 Y.issued .September ,16, 1941, and the description thereof will `therefore lbe limited Ato ,only .those `parts Which-are required for a clear 4,understanding fof ithe present finvention,

.The brake vapplication `.valve portion II comprises a vpiston 2l, aslide valve 22^movablewith said piston, and va'spring'23 acting xonsaid piston for moving same and the slide valve 22 to their normal position in which :they are zshown. The slide valve l,22 is contained ina valve chamber 2'4 which is normally charged with .-uid .under-pressure from the :feed valve device 2 in fthe usual manner through a pipe 28 :and the .usual passages in -the -pipe :bracket portion 12Uaand the application 'valve Aportion lof .the train -control valve device. At the -opposite `side of 'the piston -2I there is provided a chamber which ,contains the -spring 23 .and=which is `connected Ito :a passage 26 leading to a pipe 21 which is'adapted to be connected to means (not shown) ,controlled by .changes insignal indications Lalong the -track- Way.

When the ltrack signal `'is favorable the 4signal controlled means just referred to Ais adapted to close a vent from `the pipe 21=so that Vsaid pipe and thereby the Ychamber '25 may be charged with fluid by way of Aa restricted charging port 56 in 'the piston 2l, Vat the `same pressure as that acting in valve chamber 24; 1n `case the track signal becomes unfavorable the :signal -controlled means referred to is adapted to vent pipe 21 and thereby vent `fluid-under pressure lfrom the chamber 25 so that fluid at feed valve pressure acting inthe valve chamber 24 `will move -the piston 2I and thereby the -slide valve '22 .from their normal position ,to .an :application position 4for effecting an automatic application of the brakes on the train. The application position may be defined by engagement of piston 2l with the end wall of chamber 25. When the signal condition again becomes favorable the piston chamber 25 will again be charged with fluid under pressure through the port 56, and spring 23 will then move the piston 2| and slide valve 22 back to their normal position. A further description of the control of the application piston 2I and slide valve 22 is not considered essential in the present application.

The cut-ofi valve portion 8 comprises a piston 3D, a cut-off valve 3| connected to said piston by astem 32 which extends through a chamber 33 at one side -o'f 'said piston and through a bore 34 connecting said chamber to a chamber 35 containing the valve 3l.

The ,chamber 35 is in constant open communication with a passage 51 leading to the seat for the slide valve 22 in the application valve portion, which lpassage :is connected to a passage and pipe 58 leading 'to lthe engineer's brake valve device y3. The :chamber v33 is in constant open communication with the brake pipe 4 by way of apassage andpipe 59.

In chamber35 there is provided aseat rib 36 encircling the -bore 34. This seat rib is provided for engagement -by the vcut-oli? valve 3l to close communication between the chamber 35 and the bore 34 open to chamber 33. At the opposite side of piston 30 there islprovidedachamber 31 containing 'a spring 38 acting .on the piston for urging Vsame andthereby'thecut-o V'valve 3| to the position fin which they are shown in which posi tion said lvalve is spaced from seat rib 35 establishingcommunication between chambers 33 and 35.

Thechamber 31 is connected by way of a passage 39 to a bore 4D, which bore is open atene end to a chamber '4I land at the opposite .end to a chamber 42 which latter chamber isconnected tothe atmosphere by lway-of a passage 43. -In chamber 4I there is provided a seat'rib 44 which encircles one end of the bore 40 and which is arranged Yfor engagement by a valve piston 45 to close communication between chamber 4I and the bore 40. The chamber 4I is connected to a passage 46 leading tofthe seat .for the `slide valve 22 in the application valve portion 1. At the outer or face side of `the valve piston 45 there is provided a chamber 41 'which is also connected to passage 46 by way'of alpassage-48.

The valve Ypiston 45 is provided with a stem 49 which extends through bore 40 and chamber 42 and at its end engages one face of a flexible diaphragm 50 which, together with the casing forms the chamber 42. The diaphragm 50, due to its inherent Aelasticity 'is adapted to engage a seat rib 5I contained in chamber 42 and encircling :one end of the bore 40 to close communication between chamber 42 and the bore 4U.

At thefopposite side of the diaphragm 50 there is provided a chamber 42 which lis in constant `open communication vwith a. pipe 53 leading to the train signal pipe 5.

Operation of the embodiment shown in Fig. 1

In operation duid under pressure is supplied in the usual manner to the main reservoir I, and from thence ows lto a "pipe '55 'leading to the feed valve device '2. The feed valve device operates to supply fluid from the main reservoir pipe 55 to vthe feed valve pipe 16 at a pressure desired to be carried in the brake pipe 4. Fluid pressure thus supplied to pipe 16 flows through passage I4 and past ball check valve I5 in the brake valve device 3 to the rotary valve chamber I3 and also ows through pipe 28 to the slide valve chamber 24 in the application valve portion of the train control valve device as will be understood.

Fluid under pressure thus supplied to chamber 24 flows through the restricted port 56 in the piston 2l to chamber 25, and assuming that the means (not shown) controlled by track signals is in condition to permit the train to operate, the uid pressure in chamber 25, passage 26 and pipe 21 equalizes with that in valve chamber 24 and thus permits the spring 23 to hold the application piston 2| and slide valve VV22 in their normal position as shown.

With the brake valve handle I1 and thereby the rotary valve I6 in their normal or running position shown, fluid supplied to rotary valve chamber I3 flows through a port 60 in said valve to a passage 6I and thence through connected pipe and passage 58 and passage 51 to the cut-off valve chamber 35 in the train control valve device and also to the seat of the slide valve 22.

pressure is supplied to the train signal pipe in the usual well known manner, from whence it flows by way of pipe 53 to the chamber 52 in the brake pipe cut-oi valve portion. Fluid under pressure supplied to chamber 52 causes the diaphragm 50 to iiex upwardly into sealing engagement with the seat rib 5I. The upward movement of the diaphragm acting through the stem 49 to unseat the valve 45 from the seat rib 44.

Since the diaphragm 50 is maintained in sealing engagement with the seat rib 5I, by signal pipe pressure, communication between the bore 40 and the chamber 42 is closed, thus the valve 45 is maintained in its unseated position as shown in Fig. 1 of the drawings, and uid under pressure supplied to chamber 4| flows therefrom past the unseated valve 45 to the bore 40 from whence it flows to the chamber 31 by way of passage 39. The chamber 31 is thereby charged with fluid at feed valve pressure, which fluid pressure acting in conjunction with the pressure of spring 38 on piston 30 moves the piston and thereby the cut-olf valve 3I to the open position as shown in the drawings. In this position of the cut-01T valve 3l fluid at feed valve pressure, supplied to chamber 35, flows through bore 34 to chamber 33 and from thence to the brake pipe by way of passage and pipe 59 for charging the brake pipe on the locomotive and cars of the train.

Application of the brake in response to change in signal indication If when the brake valve handle I1 is in release position and the brakes on the locomotive and train are released, the traffic conditions become unfavorable, the consequent change in signalindication acts to effect venting of fluid under pressure from the application piston chamber 25 through passage 26 and pipe 21, and as a result the pressure in the valve chamber 24 moves the piston 2I and thereby the slide valve 22 from their normal position, in which they are, shown, to their application position.

In the application position of the slide valve 22 passage 46 leading to the chambers 4I and 41 in the brake pipe cut-oil valve portion 1 is connected to an atmospheric passage 65 by way of passages 66, 61, and 68 in the slide valve. With 4this communication established uid under pressure in chamber 31 is vented to the atmosphere by way of passage 39 in the brake pipe cut-01T valve portion, bore 40, past unseated valve 45, chamber 4I, passage 46, passages 66, 61, and 68 in the slide valve 22 and atmospheric passage 65. The reduction in the pressure in chamber 31 due to the venting of uid under pressure therefrom as just described, permits brake pipe pressure acting in chamber 33 to move the piston in a direction to pull the cut-off valve 3| into engagement with seat rib 36, thereby cutting off the supply of uid under pressure from the main reservoir to the brake Ipipe 4 by way of the rotary valve I6. As a result of this reduction in brake pipe pressure a service application of the brakes on the train is automatically obtained in the manner fully described in the aforementioned Hewitt and McNeal patent. Since this invention is not concerned with the operation of the equipment to effect a service application of the brakes it is therefore deemed unnecessary to describe the operation.

From the above it will be apparent that, in the event of a suddent reduction in brake pipe pressure, caused, for instance, by a ruptured brake pipe during the time application of the brakes is being effected by the operation of the automatic train control valve device in response to a change in signal indication, the brake pipe cut-oli valve 6 will operate to prevent loss of fluid under pressure from the main reservoir I.

When it is desired to effect a release of the brakes, after an application has been eiected by the automatic train control valve device, and the equipment is conditioned therefore, the brake pipe will be recharged with iiuid under pressure in the manner hereinbefore described in connection with initially charging.

If the train should part, the train signal pipe pressure will be reduced and consequently the pressure in chamber 52 of the brake pipe cutolf valve portion 1 in the train control valve device 6 will belikewise reduced. Upon reduction in the pressure of fluid in chamber 52 the pressure of uidin the bore 40 will cause the diaphragm 50 toy eX downwardly, out of engagement with the seat rib 5I and thereby establish communication between the bore 40 vand the chamber 42. Downward movement of diaphragm 51) will permit the valve to move downwardly into seating engagement with the seat rib 44 thus cutting off communication between the bore 46 and the chamber 4 I If the engineers brake valve device is in release position and the associated parts of the brake oif the supply of uid under pressure from the rotary valve I6 to the brake pipe 4 and, as a consequence, stops the flow of uid under pressure from the main reservoir to the brake pipe until the pressure is again restored in chamber 52.

If the train should part at a time when the cutoff valve 3i is in its cut-ofi position by reason of operation of the application Valve, as previously described, the venting of fluid under pressure from chamber 52 will insure that the cut-offl valve 3| will be maintained closed until the pressure is again restored in the train signal pipe and chamber 52.

From the foregoing description it will be apparent that the brake pipe cut-off valve device 8 is operative to cut-oil the supply of fluid under pressure from the main reservoir to the brake pipe 4 upon either the operation of the application valve portion 'l of the train control valve device I or by a break-in-two of the train.

Description of the embodiment shown in Fig. 2

In Fig. 2 there is Villustrated another form of the invention shown in Fig. 1 in which certain modications are made in the piping arrangement leading to the brake pipe cut-01T valve portion 8 of the automatic train control valve device 6. For simplicity, corresponding parts and pipes of the two embodiments will be designated by the same reference numerals without further description and only those parts provided in Fig. 2 which are not provided in the previous embodiment will be described.

In this embodiment of the invention, the train signal pipe 5 which is connected to the pipe 53 in the first embodiment of the invention is omitted and a double check valve device is employed which is constructed and arranged to selectively connect the pipe 53, leading to the chamber 52 of the brake pipe cut-off valve portion 8, to either a pipe |0| connected to one end of the check valve device and leading to the brake pipe 4 or to a pipe |02 connected to the opposite end of the check valve device and leading to the usual locomotive sanding pipe |03. It will be noted that the pipe 53 is connected to the side outlet passage of the check valve device through a uniflow Check Valve ||6 and also through a restricted communication ||1 which by-passes the check valve ||6 for a reason hereinafter described.

In this embodiment of the invention the automatic train control valve device 6 is identical with that shown and described inthe previous embodiment and for this reason no further description here is deemed necessary.

The engineers brake valve device is also identical to that shown in the previous embodiment and, as before mentioned, in connection with the previous embodiment, may be of the type disclosed in Patent No. 2,106,483 issued to Ellis E. Hewitt on January 25, 1938.

As is well known by those skilled in the fluid pressure brake art, the operating handle is of the safety control type which is movable in a vertical plane, and is operative upon downward movement from the' normal position shown, in all brake controlling positions of the handle, to actuate a sanding bail |04 which is mounted to pivot on a shaft secured in the brake valve casing.

.The sanding bail is arranged to engage the stem of a sand valve |06 upon downward movement of the bail for unseating said valve against the opposing force of a spring |07, the Spring being of the handle I1 to its normal position.

The sand valve isV contained in a chamber |08 which is connected kby way of a passage |00 to the fluid pressure supply passage |4 which, as described in the rst embodiment, is supplied with iiuid from the main reservoir at a reduced pressure through the feed Valve device 2. The stem of the valve |06 extends through a passage ||0 which is connected to the sand pipe |03, which passage is also connected to the atmosphere by way of a restricted passage The valve |06 when unseated admits fluid under pressure from chamber |08 to the passage H0, from which passage uid under pressure flows to the atmosphere at a restricted rate through passage III and also flows to the sand pipe |03. When seated the valve |06 prevents the flow of fluid from chamber |08 to passage |I0. The restricted atmospheric passage is provided for the purpose of normally maintaining the sand pipe |03 and pipe |02 at atmospheric pressure. It will be apparent that this atmospheric communication from the passage I0 will prevent leakage of fluid past the valve |06 when the valve is seated from building up a pressure in the pipes |03 and |02 and consequently in the check valve chamber which is open to the pipe |02.

Operation of the embodiment shown in Fig. 2

It will be understood that fluid under pressure supplied from the feed valve device 2 to the passage 4 in the manner hereinbefore described, flows to chamber |08 by way of passage |09. It will also be understood that with the brake valve handle in release position as shown, and the automatic train control valve device in its release position, the cut-oir valve 3| of the brake pipe cut-off valve portion 8 will be unseated and fluid under pressure will iiow from the passage 51 to the brake pipe 4- in a manner already described in connection with the embodiment of the invention shown in Fig. l of the drawings.

Fluid under pressure thus supplied to the brake pipe 4 flows therefrom to the pipe |0| leading to one side of the check valve device |00. The iiuid pressure in pipe |0| then shifts a double check valve |5 in the device to a position for closing communication between pipe |02 and pipe 53 and for connecting the pipe I0 to the pipe 53, whereupon iiuid flows from pipe |0| past the right hand end of the check valve ||5, as' viewed in the drawings, and through uniiiow check valve ||6, side outlet passage to the pipe 53. At the same time fluid supplied to the side outlet passage of the check valve |00 flows through the restricted passage ||1 to the pipe.

53. Fluid under pressure thus supplied to pipe 53 flows therefrom to the chamber 52 in the brake pipe cut-off valve portion 8 causing the diaphragm to be maintained in engagement with the seat rib 5| to maintain closed the communication between bore 40 and chamber 42.

O peration of the application portion 1 of the train control valve device 6 to application position to eiect an application of the brakes will operate in the same manner as hereinbefore described to vent iiuid under pressure from chamber 3'1 in the brake pipe cut-off valve device to cause the cut-oir valve 3| to close communication from the main reservoir to the brake` duce correspondingly, and as a consequence the pressure in chamber 52 is reduced by Way of pipe 53, restricted passage II'I and past the unseated end of the check valve II5. A reduction in pressure in chamber 52 permits the fluid at brake pipe pressure acting in bore 45 to move the diaphragm 5|) out of engagement with the seat 5|, thus Venting fluid under pressure from chamber 3'I to cause the cut-off Valve to close communication between the main reservoir I and the brake pipe in the manner already described in connection with Fig. 1 of the drawings.

It will be noted that the ow of fluid under pressure from chamber 52 to the pipe ISI is controlled by the restricted passage II'I so as to delay, for an interval of time, operation of the brake pipe cut-01T valve in the event of a slight over reduction in brake pipe pressure during a service brake application.

From the foregoing description of the operation of the embodiment shown in Fig. 2 it will be understood that a sudden reduction in brake pipe pressure causes the brake pipe cut-off valve portion oi the automatic train control valve device to operate automatically to cut oi the flow of fluid under pressure from the main reservoir I to the brake pipe 4. From this it will be apparent that main reservoir pressure cannot be depleted nor can the brakes on the head end of the train be released, when an emergency application of the brakes is effected, by flow of fluid under pressure from the main reservoir to the brake pipe.

If, at any time, the operator desires to recharge the brake pipe and thereby eect a release of the brakes following an emergency application, he may depress the brake valve handle |'I and thereby operate the bail |04 to move the valve stem in a downwardly direction for unseating the sand valve |06. When the sand valve IIJt` is unseated, fluid from the supply passage I4 ows to chamber |38 and then past unseated valve |06 to passage IIU.

Fluid under pressure thus supplied to passage I I ows to the left hand side of the check valve device IUD as viewed in the drawings by way of sand pipe |03 and connected pipe |02. The fluid pressure in pipe |02 then shifts the double checkl valve II from the position in which it is shown to a position for closing communication between pipe IBI and pipe 53 and for connecting the pipe |92 to the pipe 53. With this communication claim as new and desire to secure by Letters Patent, is:

l. In a fluid pressure brake equipment for a train of vehicles, in combination, a main reservoir, a brake pipe, a feed valve device, an engineers brake valve device having a release position in which iiuid under pressure may flow from the feed valve device to the brake pipe, valve means controlling communication through which fluid supplied by the feed valve device flows from said brake valve device to said brake pipe, means responsive to an unfavorable track signal to effect operation of said valve means to close said communication, a normally charged control pipe arranged to be vented of fluid under pressure incident to a break-in-two of the train to effect `a reduction in the pressure of fluid therein, and means responsive to the reduction in Ipressure in said control pipe to also eect operation of said valve means to close said communication.

2. In. a uid pressure-brake equipment, ir combination, a brake pipe, a brake valve device having a position for establishing a communication through which uid under pressure is supplied to said brake pipe, a valve for controlling said communication, a piston connectedto said valve and sure to close said valve, a control pipe normally established uid ows from the pipe |02 to the chamber 52 past the unseated end of the check Valve II5, past uniflow check valve II6 and also through the restricted passage I II to the pipe 53.

Upon an increase in the pressure of fluid in chamber 52 the diaphragm 50 is moved into sealing engagement with the seat rib 5I to cut oi communication between the bore 4,0 and the chamber 42, whereupon fluid under pressure is supplied to the chamber 3l as described in initially charging in connection with the description of the operation of the first embodiment. Fluid under pressure supplied to chamber 3l together with the force of spring 38 causes the charged with uid under pressure, and means responsive to a reduction in pressure in said control pipe to also vent fluid under pressure from the second mentioned chamber for rendering said piston operable by brake pipe pressure to close said valve.

3. In a uid pressure brake equipment, in combination, a brake pipe, a brake valve device having a position for establishing a communication through which fluid under pressure may be supplied to said brake pipe, a cut-01T valve for controlling said communication, a valve mechanism having a, normal position for effecting operation of said cut-off valve to open Said communication and movable to another position for eiecting operation of said cut-oil Valve to close said communication, a control pipe normally charged with iiuid under pressure, and valve means subject to the pressure of fluid in said control pipe and operative upon a reduction in the pressure of fluid in said control pipe for also effecting operation of said cut-oli valve to close said communication.

4. In a fluid pressure brake equipment for a train comprising a plurality of coupled vehicle units, in combination, a brake pipe, a brake valve device having a position for establishing a communication through which uid under pressure may be supplied to said brake pipe, a cut-off valve forcontrolling said communication, a valve mechanism having a normal position for effecting operation of said cut-01T valve to open said communication and movable to another position for eiiecting operation of said cut-off valve to close said communication, a control pipe normally charged with fluid undervpressure, said control pressure upon the parting of two of said coupled vehicle units of the train Vto effect a reduction in the pressure of fluid thereimand valve means subject to the pressure of fluid in said control pipe and operative upon the reduction in the pressure aof fluid in said control lpipe for effecting operation of said cut-offvalve to close said communication with said valve` mechanism in its normal position.

5. In a fluid pressure brake equipment, in combination,- a brake pipe, Va brale valve device for supplying fluid under pressure to said brake pipe, a cut-off valve `for`controlling communication through which fluid is supplied from said brake valve device to said brake pipe, a chamber a piston connected to said cut-off valve and responsive tothe pressure 'o'f`fluid in said chamber, means responsive toa favorable signal indication for supplying fluidA under pressure to said chamber for' rendering'said piston 'operative to open said cut-off valve and responsive to an unfavorable signal' indication for venting fluid under pressure fromsaidcharnber' for rendering said piston oprative'tc closejsaid'cut-of valve, valve means having anormal position for opening communication'between'saldchainber and said means and movablefto another position for closing communication between said chamber and said means and for openingccminuni'cation between said chamber and the atmosphere for rendering said piston operative"'tof'c`lose said cut-off valve even though the first mentioned means is responsive to a favorable signal indication, and means including"aflexibl'dia'phr'agin'responsive to fluid under pressure supplied thereto for maintaining said valve means in 4itsnormal position and upon the release of fluid under. pressure therefrom for moving said valve'rneans to said other position.

6. In a fluid pressure brake equipment, in combinatlion, a brakepipe, afbral'e valvev device for supplying fluid under pressure to said brake` pipe, a cut-off valve fo',` controlling communication through Which fluidl is" supplied from said, brake valve' device to 'said brake pipe, a chamber, a piston connected to said cut-off valveI and responsive to the pressure of fluid in saidA chamber, means responsive toa a favorable signal indi-A cation for supplying fluid under pressure to said chamberfor rendering 'said piston ,operative to open said cut-offl valve and' responsive to an unfavorable signal indicationv for venting fluid u'nder pressure from`s'aid chamber.. for rendering ls'aid'piston 'operative' to close said cut-offvalve, valve meanshaving a normal position for` opening communication between saidA chamber an'dsaid means and movabletofanother position for closing communication.betweensaid chamber and saidrneans and for'opening communication directly from said chamber tothe atmosphere for rendering said piston operative toclose saidcutoff valve even though said means is responsive to crease in fluid pressure in said control pipe for4 operating said valve means from. its normalposltion said other position.

'7, In afluid pressure brake equipment. in combination, a brake pipe, a'bral'e valve devicehaving"` a p position for establishing a communication. through Whh ld @impressum vis supplied lia,

Seid brakepipe. valve means controlling said communication, means responsive to an unfavorable track signal to effect operation of said valve mgas t0 @105.8 ,Said communication. a train slsnall pipe normally charged with fluid under pressure, and means responsive to a reduction in pressure in said signali pipe to also effect operation ai Said valve means t9 close Asaid communication. n 3 .In a fluid blessure brake equipment. in combination, a brake pipe, a braise valve device hava'position for establishing a communication through which fluid under pressure is supplied to said brake pipe, valve means controlling said communication, means responsive to an unfavorable tflck, Signal t0 8.38ct. Operation. of said valve means t0 Close Said. communication. a train signal pipe normally charged with fluid under pressure, and means including a flexible diaphragm responsive to the pressure of fluid in said signal pipe and operative upon a reduction in pressure in said signal pipe to also effect operation of said valve means to closel said communication.

Si. In a fluid pressure brake equipment, in combination, a brake pipe, a brake valve .device for supplying fluid under pressure to said brake pipe,

a' communication through which fluid under pressure isy supplied from said brake valve device tosaidA brake pipe,v valve means having a normal QQ, position for opening said communication and movable to another positionfor closing said communication, piston means forl actuating said valve means from said normal position to said other position, a signal pipe normally charged with QQ, fluid under pressure, meansI operative incident to an unfavorable tracl;v signal to cause said piston means to actuate said Valve means. from said normal position to said other position, and means operative incidenty to a, reduction in signal pipe QQ pressure to also cause said piston means to actuate said valve means from said normal position to said other position.

10. In a fluid pressure. brake equipment, in combination, a brake pipe. a brake valve device fori supplying fluidl under pressure to said brake charged with, fluid, under,V pressure, and valveA means subject toA the pressure ofv fluid in said signalpipe andl operative upon aA reduction in the,pressureI of fluid in said signal pipe for effecting operationA ofsaidy cut-olf; valve to` close Said, communiaiqawiihseidlvalve mechanism in itsvnorrnal position.

11 111 a fluid largeurs.v brake. equipment;` iny combination,r a brale pipeya brake valve device,

for supplying fluid ,under pressure to said brake pipe, a cut-off valve for controlling communication through which fluiddisI Supplied from said brake valve device to s aid brake pipe, achamber, a piston for actuating to saidcut-of valve, a valve mechanism havingrone position for supplying fluid under Drssuretosaid chamber for effecting the operation ofsaid pistonto open said,

cut-off valve and havingv another position for ventingfluid'under pressure from said chamber for'effectingthe operation of said piston to closeV said cut-oil valve, means having a flrst position for opening-communication between said valve pipe pressure for effecting operation of said means to said second position and upon an increase in pressure in said signal pipe for effecting operation of said means to said first position.

12. In a uid pressure brake equipment, in combination, a brake pipe, a brake valve device having a position for establishing a communication through which fluid under pressure is supplied to said brake pipe, valve means controlling said communication, means responsive to an unfavorable track signal to eifect operation of said valve means to close said communication, a control pipe normally charged with fluid under pressure from said brake pipe, means responsive to a reduction in pressure in said control pipe to also effect the operation of said valve means to close said communication, and means interposed between said control pipe and said brake pipe for controlling the rate of reduction in pressure in said control pipe upon a sudden reduction in brake pipe pressure.

13. In a iiuid pressure brake equipment, in combination, a brake pipe, a brake valve device having a position for establishing a communication through which fluid under pressure is supplied to said brake pipe, valve means controlling said communication, means responsive to an unfavorable track signal to eifect operation of said valve means to close said communication, a control pipe normally charged with uid under pressure from said brake pipe, means responsive to a reduction in pressure in said control pipe to also effect the operation of said valve means to close said communication, and means including a choke interposed between said control pipe and said brake pipe for controlling the rate of reduction in pressure in said control pipe upon a reduction in brake pipe pressure.

14. In a fluid pressure brake equipment, in

combination, a brake pipe, a brake valve device r having a position for establishing a communication through which uid under pressure is supplied to said brake pipe, valve means controlling said communication, means responsive to an unfavorable track signal to effect operation of said valve means to close said communication, a control pipe normally charged with uid under pressure from. said brake pipe, a uniow check valve interposed between said control pipe and said brake pipe for permitting flow of fluid from said brake pipe to said control pipe, means responsive to a reduction in pressure in said control pipe to also eiect operation of said valve means to close said communication, and a choke interposed between said control pipe and said brake pipe for controlling the rate of reduction in pressure in said control pipe upon a reduction in brake pipe pressure.

15. In a iiuid pressure brake equipment, in combination, a brake pipe, a brake valve device for supplying iiuid under pressure to said brake pipe, a cut-off valve for controlling communication through which fluid is supplied from said brake valve device to said brake pipe, a valve mechanism having a normal position for effecting operation of said cut-off valve to open said communication and movable to another position for effecting operation of said cut-off valve to close said communication, a control pipe normally charged'with uid under pressure from the brake pipe, means interposed between the brake pipe and the control pipe for controlling the rate of reduction in pressure in said control pipe upon a reduction in brake pipe pressure, and valve means subject to the pressure of fluid in said control pipe and operative upon a reduction in the pressure of iiuid in the control pipe for effecting operation of said cut-off valve to close said communication with said valve mechanism in its normal position.

16. In a fluid pressure brake, in combination, a brake pipe, brake pipe charging control means for supplying fluid under pressure to said brake pipe, a chamber, a cut-off valve controlling communication through which iiuid under pressure' charging of said brake pipe to admit fluid under pressure to said chamber to increase the pressure in the chamber and providing for re- 'lease of fluid Linder pressure from said chamber upon a reduction in brake pipe pressure to eifect a reduction in the pressure in the chamber, and means operative to supply fluid under pressure to said chamber with said brake pipe vented.

17. In a iiuid pressure brake, in combination, a brake pipe, brake pipe charging control means for supplying fluid under pressure to said brake pipe, a chamber, a cut-off valve controlling communication through which iiuid under pressure is supplied from said brake pipe charging means to said brake pipe and operative upon an increase in the pressure of iiuid in said chamber to open said communication and upon a reduction in the pressure of fluid in said chamber to close said communication, means operative by nuid under pressure in said brake pipe to open said chamber to said brake pipe and operative by uid under pressure supplied through another pipe with said brake pipe vented to open said chamber to said other pipe, and means for supplying fluid under pressure to, said other pipe.

18. In a iiuid pressure brake, in combination, a brake pipe, brake pipe charging control means for supplying fluid under pressure to said brake pipe, a chamber, a cut-off valve controlling communication through which uid under pressure is supplied from said .brake pipe charging means to said brake pipe and operative upon an increase in the pressure of fluid in said chamber to open said communication and upon a reduction in the pressure of fluid in said chamber to close said communication, another pipe a double check valve device having its end outlets open respectively to said brake pipe and said other pipe and its side outlet open to saidv chamber. and means for supplying fluid under pressure to and releasing iiuid under pressure from said other pipe.

19. In a fluid pressure brake, in combination, a brake pipe, brake pipe'charging control means for supplying iiuid under pressure to said brake pipe, a chamber, a cut-off valve controlling communication through which fluid under pressure is supplied from said brake pipe charging means to said brake pipe and operative upon an increase in the pressure of duid in .said chamber to open said communication and upon a ,reduction in the pressure of fluid in said chamber to close said communication, another pipe, means for supplying iiuid under pressure to and .releasing fluid under pressure from `said otherY pipe, and a check valve device operative by the pressure of fluid in said other pipe for connecting said other pipe to and isolating said brake pipe from said chamber.

20. In a iiuid pressure brake, `in combination, a brake pipe, another pipe, an engineers brake valve device for supply-ing fluid under pressure to said brake pipe and also operative tosupply uid under pressure to said otherpipe, -a fchambena cut-off valve controllingv communication through which fluid under pressure is ,suppliedfrom said brake valve device to said brake pipe 'and Operative upon an increase inthe .pressure 'of iluid in said chamber to open said lcommunication and upon a decrease in hepreSSure of fluid in said chamber to close said communication, means operative by fluid under pressure in said brake pipe to admit fluid under pressure from lsaid .brake pipe to said chamberand operative when .thepressure of iiuid in said other pipe is-inexcess :of brake pipe pressure to admit fluid under; pressure from said other pipe to said chamber.

2l. Ina fluid pressure brake `in combination,` a brake pipe, another pipenorrnally open to Vthe atmosphere, a brake valve device for supplying fluid -under pressure to said brake pipe-and vccmprising a handle which is rdepressible by thereugineer at his discretion for supplyinglluid .under pressure to Said otherpipe, sa` chamber, a cutoff valve controlling communication .through 'which fluid under pressure is -supplied fromsaid-.brake valve device to. said brake pipe, and loperative upon the supply of lfluid under pressure tousaid chamber to opensaidcommunication and upon a release of fluid under pressure ffromsaid Achamber to close said communication, and fa double check valve operative Aby iiuid `under `pressure in said brake ,pipe to Open said chamber to .said brake pipe and operative by uid under pressure supplied through said other pipe with said brake pipe vented to open said chamber to said other pipe.

'22. ay uid pressure brake equipment com prising a plurality of coupled vehicle units, 1n combination, a brake pipe, brake pipe charging .control means having a position for vestablishing a communication through which iluid under ,pressure may be supplied to said brake pipe, valve means `for controlling said communication, a .valve mechanism having a normal position for effecting operation of said v alve means to open I said communication and movable to another position for effecting operation of said valve means to close said communication, a normally charged control pipe arranged to be vented of fluid under -pressure .uponthe parting of two coupled vehicle units in a train tov effect a reduction in the pressure of fluid therein, .and means responsive to the reduction in pressure in said control pipe to also effect operation of said valve means to close said communication.

23. Ina fluid pressure brake equipmentl for .a train of coupled vehicles, in combination, a brake pipe, brake pipe charging control means for supplying lfluid under pressure to said brake pipe, valve means controlling communication through which uid is supplied from said brake pipe charging control means to said brake pipe, means having va normal position for eecting operation ofsald Valve means to open .said communication and movable toanother position for effecting operation of vsaid valve' means to close said communication, a normally charged control pipe arranged to be vented of fluid under pressure incldent to a'break-inftwo of the train to effect a reduction vin the Lpressure of liuid therein, and other means responsive to the reduction in pressure in said control pipe to also effect operation of said valve means to close said communication.

JOHN N. GCOD. 

